In the past, a wireless power transfer system has been known which includes a power transmission apparatus configured to wirelessly transmit power and a power reception apparatus configured to receive power supplied from the power transmission apparatus. In some wireless power transfer systems, a power transmission apparatus may detect a power reception apparatus within a range to which the power transmission apparatus is capable of transmitting power and transmit power to the detected power reception apparatus.
PTL 1 discloses a technology in which a power reception apparatus notifies its ID and apparatus type to a power transmission apparatus so that authentication processing may be performed between the power reception apparatus within a power transmittable range of the power transmission apparatus and the power transmission apparatus.
In a case where a plurality of power transmission apparatuses are closely placed and the plurality of power transmission apparatuses have overlapping communication ranges for performing communications required for wireless power transfer such as exchange of control information and authentication processing, a power reception apparatuses may possibly communicate with a power transmission apparatus different from a power transmission apparatus desired by the power reception apparatus to receive power from.
A case will be described in which a first power transmission apparatus and a second power transmission apparatus are placed at positions where their communication ranges overlap each other and a first power reception apparatus is positioned within the power transmission range of the first power transmission apparatus and a second power reception apparatus is positioned within the power transmission range of the second power transmission apparatus, for example. When the first power reception apparatus and the second power reception apparatus broadcast messages for establishing a communication connection, the messages are received by the first power transmission apparatus and the second power transmission apparatus.
Though the first power transmission apparatus is originally not required to transmit power to the second power reception apparatus which is not placed within the power transmission range of the first power transmission apparatus, the first power transmission apparatus having received the message from the second power reception apparatus may possibly establish a communication connection for executing a wireless power transfer to the second power reception apparatus. Similarly, though the second power transmission apparatus is originally not required to transmit power to the first power reception apparatus which is not placed within the power transmission range of the second power transmission apparatus, the second power transmission apparatus having received the message from the first power reception apparatus may possibly establish a communication connection for executing a wireless power transfer to the first power reception apparatus. This improperly established communication connection may cause unnecessary processing for power transmission.